The Complexity of Angular Resolution
Vol. 27, no. 7, pp. 565-580, 2023. Regular paper.
Abstract The angular resolution of a straight-line drawing of a graph is the smallest angle formed by any two edges incident to a vertex. The angular resolution of a graph is the supremum of the angular resolutions of all straight-line drawings of the graph. We show that testing whether a graph has angular resolution at least $\pi/(2k)$ is complete for $\exists\mathbb{R}$, the existential theory of the reals, for every fixed $k \geq 2$. This remains true if the graph is planar and a plane embedding of the graph is fixed.

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Submitted: July 2022.
Reviewed: July 2023.
Revised: August 2023.
Accepted: August 2023.
Final: August 2023.
Published: August 2023.
Communicated by Michael Kaufmann
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